Department of Psychology, Sun Yat-sen University, Guangzhou, China; Center for Functional Neuroimaging, Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
Laboratory of Applied Brain and Cognitive Sciences, Shanghai International Studies University, Shanghai, China; Center for Functional Neuroimaging, Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
Neuroimage. 2019 Jun;193:157-166. doi: 10.1016/j.neuroimage.2019.03.016. Epub 2019 Mar 17.
Arterial spin labeled (ASL) perfusion magnetic resonance imaging (MRI) is increasingly used to assess regional brain activity and cerebrovascular function in both healthy and clinical populations. ASL perfusion imaging provides a quantitative measure of regional brain activity by determining absolute cerebral blood flow (CBF) values at a resting state or during task performance. However, the comparative reliability of these ASL measures is not well characterized. It is also unclear whether the test-retest reliability of absolute CBF or task-induced CBF change measures would be comparable to the reliability of task performance. In this study, fifteen healthy participants were scanned three times in a strictly controlled in-laboratory study while at rest and during performing a simple and reliable psychomotor vigilance test (PVT). The reliability of absolute CBF and task-induced CBF changes was evaluated using the intraclass correlation coefficient (ICC) and compared to that of task performance. Absolute CBF showed excellent test-retest reliability across the three scans for both resting and PVT scans. The reliability of regional absolute CBF was comparable to that of behavioral measures of PVT performance, and was slightly higher during PVT scans as compared with resting scans. Task-induced regional CBF changes demonstrated only poor to moderate reliability across three scans. These findings suggest that absolute CBF measures are more reliable than task-induced CBF changes for characterizing regional brain function, especially for longitudinal and clinical studies.
动脉自旋标记（ASL）灌注磁共振成像（MRI）越来越多地用于评估健康和临床人群的局部脑活动和脑血管功能。ASL 灌注成像通过在静息状态或任务执行期间确定局部脑血流（CBF）的绝对值来提供局部脑活动的定量测量。然而，这些 ASL 测量的比较可靠性尚未得到很好的描述。也不清楚绝对 CBF 或任务诱发的 CBF 变化测量的测试 - 重测可靠性是否与任务表现的可靠性相当。在这项研究中，15 名健康参与者在严格控制的实验室研究中进行了三次扫描，同时在休息和执行简单可靠的精神运动警觉性测试（PVT）时进行扫描。使用组内相关系数（ICC）评估绝对 CBF 和任务诱发的 CBF 变化的可靠性，并与任务表现的可靠性进行比较。绝对 CBF 在三次扫描的静息和 PVT 扫描中均表现出极好的测试 - 重测可靠性。区域绝对 CBF 的可靠性与 PVT 表现的行为测量相当，在 PVT 扫描期间略高于静息扫描。任务诱发的局部 CBF 变化仅在三次扫描中表现出较差到中等的可靠性。这些发现表明，绝对 CBF 测量比任务诱发的 CBF 变化更可靠，用于表征局部脑功能，特别是对于纵向和临床研究。
